From the past, a number of improvements were made on two-piece golf balls. The main requirements on golf balls by players are concerned in distance, control and feel. Ordinary players make much of distance whereas skilled players set controllability above distance.
For golf balls, there were made a number of proposals for improvements in distance and controllability. For example, JP-A 10-127823 discloses a golf ball comprising a solid core and a cover which is improved in flight performance, controllability and feel by specifying the gage and JIS-C hardness of the cover and the type of solid core material and reducing the hardness difference between the solid core and the cover. JP-A 11-290479 discloses a golf ball which is improved in flight performance, controllability and feel by optimizing the hardness distribution and deflection or deformation of the core and the gage of the cover.
Since these proposals lay greatest store on distance increase, the cover is relatively hard. On use by skilled players, these balls receive less spin on approach shots and there is left a room for further improvement in controllability.